Make closures carry their own ClosureKind
Right now, we use the "`movability`" field of `hir::Closure` to distinguish a closure and a coroutine. This is paired together with the `CoroutineKind`, which is located not in the `hir::Closure`, but the `hir::Body`. This is strange and redundant.
This PR introduces `ClosureKind` with two variants -- `Closure` and `Coroutine`, which is put into `hir::Closure`. The `CoroutineKind` is thus removed from `hir::Body`, and `Option<Movability>` no longer needs to be a stand-in for "is this a closure or a coroutine".
r? eholk
Split coroutine desugaring kind from source
What a coroutine is desugared from (gen/async gen/async) should be separate from where it comes (fn/block/closure).
`IntoDiagnostic` defaults to `ErrorGuaranteed`, because errors are the
most common diagnostic level. It makes sense to do likewise for the
closely-related (and much more widely used) `DiagnosticBuilder` type,
letting us write `DiagnosticBuilder<'a, ErrorGuaranteed>` as just
`DiagnosticBuilder<'a>`. This cuts over 200 lines of code due to many
multi-line things becoming single line things.
Currently, `emit_diagnostic` takes `&mut self`.
This commit changes it so `emit_diagnostic` takes `self` and the new
`emit_diagnostic_without_consuming` function takes `&mut self`.
I find the distinction useful. The former case is much more common, and
avoids a bunch of `mut` and `&mut` occurrences. We can also restrict the
latter with `pub(crate)` which is nice.
Renamings:
- find -> opt_hir_node
- get -> hir_node
- find_by_def_id -> opt_hir_node_by_def_id
- get_by_def_id -> hir_node_by_def_id
Fix rebase changes using removed methods
Use `tcx.hir_node_by_def_id()` whenever possible in compiler
Fix clippy errors
Fix compiler
Apply suggestions from code review
Co-authored-by: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Add FIXME for `tcx.hir()` returned type about its removal
Simplify with with `tcx.hir_node_by_def_id`
detects redundant imports that can be eliminated.
for #117772 :
In order to facilitate review and modification, split the checking code and
removing redundant imports code into two PR.
`GenKillAnalysis` has five methods that take a transfer function arg:
- `statement_effect`
- `before_statement_effect`
- `terminator_effect`
- `before_terminator_effect`
- `call_return_effect`
All the transfer function args have type `&mut impl GenKill<Self::Idx>`,
except for `terminator_effect`, which takes the simpler `Self::Domain`.
But only the first two need to be `impl GenKill`. The other
three can all be `Self::Domain`, just like `Analysis`. So this commit
changes the last two to take `Self::Domain`, making `GenKillAnalysis`
and `Analysis` more similar.
(Another idea would be to make all these methods `impl GenKill`. But
that doesn't work: `MaybeInitializedPlaces::terminator_effect` requires
the arg be `Self::Domain` so that `self_is_unwind_dead(place, state)`
can be called on it.)
This results in two non-generic types being used: `BorrowckResults` and
`BorrowckFlowState`. It's a net reduction in lines of code, and a little
easier to read.
It is used just once. With it removed, the relevant code is a little
boilerplate-y but much easier to read, and is the same length. Overall I
think it's an improvement.
When encountering multiple mutable borrows, suggest cloning and adding
derive annotations as needed.
```
error[E0596]: cannot borrow `sm.x` as mutable, as it is behind a `&` reference
--> $DIR/accidentally-cloning-ref-borrow-error.rs:32:9
|
LL | foo(&mut sm.x);
| ^^^^^^^^^ `sm` is a `&` reference, so the data it refers to cannot be borrowed as mutable
|
help: `Str` doesn't implement `Clone`, so this call clones the reference `&Str`
--> $DIR/accidentally-cloning-ref-borrow-error.rs:31:21
|
LL | let mut sm = sr.clone();
| ^^^^^^^
help: consider annotating `Str` with `#[derive(Clone)]`
|
LL + #[derive(Clone)]
LL | struct Str {
|
help: consider specifying this binding's type
|
LL | let mut sm: &mut Str = sr.clone();
| ++++++++++
```
```
error[E0596]: cannot borrow `*inner` as mutable, as it is behind a `&` reference
--> $DIR/issue-91206.rs:14:5
|
LL | inner.clear();
| ^^^^^ `inner` is a `&` reference, so the data it refers to cannot be borrowed as mutable
|
help: you can `clone` the `Vec<usize>` value and consume it, but this might not be your desired behavior
--> $DIR/issue-91206.rs:11:17
|
LL | let inner = client.get_inner_ref();
| ^^^^^^^^^^^^^^^^^^^^^^
help: consider specifying this binding's type
|
LL | let inner: &mut Vec<usize> = client.get_inner_ref();
| +++++++++++++++++
```
When encountering a move error, look for implementations of `Clone` for
the moved type. If there is one, check if all its obligations are met.
If they are, we suggest cloning without caveats. If they aren't, we
suggest cloning while mentioning the unmet obligations, potentially
suggesting `#[derive(Clone)]` when appropriate.
```
error[E0507]: cannot move out of a shared reference
--> $DIR/suggest-clone-when-some-obligation-is-unmet.rs:20:28
|
LL | let mut copy: Vec<U> = map.clone().into_values().collect();
| ^^^^^^^^^^^ ------------- value moved due to this method call
| |
| move occurs because value has type `HashMap<T, U, Hash128_1>`, which does not implement the `Copy` trait
|
note: `HashMap::<K, V, S>::into_values` takes ownership of the receiver `self`, which moves value
--> $SRC_DIR/std/src/collections/hash/map.rs:LL:COL
help: you could `clone` the value and consume it, if the `Hash128_1: Clone` trait bound could be satisfied
|
LL | let mut copy: Vec<U> = <HashMap<T, U, Hash128_1> as Clone>::clone(&map.clone()).into_values().collect();
| ++++++++++++++++++++++++++++++++++++++++++++ +
help: consider annotating `Hash128_1` with `#[derive(Clone)]`
|
LL + #[derive(Clone)]
LL | pub struct Hash128_1;
|
```
Fix#109429.
When going through auto-deref, the `<T as Clone>` impl sometimes needs
to be specified for rustc to actually clone the value and not the
reference.
```
error[E0507]: cannot move out of dereference of `S`
--> $DIR/needs-clone-through-deref.rs:15:18
|
LL | for _ in self.clone().into_iter() {}
| ^^^^^^^^^^^^ ----------- value moved due to this method call
| |
| move occurs because value has type `Vec<usize>`, which does not implement the `Copy` trait
|
note: `into_iter` takes ownership of the receiver `self`, which moves value
--> $SRC_DIR/core/src/iter/traits/collect.rs:LL:COL
help: you can `clone` the value and consume it, but this might not be your desired behavior
|
LL | for _ in <Vec<usize> as Clone>::clone(&self.clone()).into_iter() {}
| ++++++++++++++++++++++++++++++ +
```
CC #109429.
Liveness data is pushed from multiple parts of NLL. Instead of changing
the call sites to maintain live loans, move the latter to `LivenessValues` where
this liveness data is pushed to, and maintain live loans there.
This fixes the differences in polonius scopes on some CFGs where a
variable was dead in tracing but as a MIR terminator its regions were marked
live from "constraint generation"
Refactor NLL constraint generation and most of polonius fact generation
As discussed in #118175, NLL "constraint generation" is only about liveness, but currently also contains legacy polonius fact generation. The latter is quite messy, and this PR cleans this up to prepare for its future removal:
- splits polonius fact generation out of NLL constraint generation
- merges NLL constraint generation to its more natural place, liveness
- extracts all of the polonius fact generation from NLLs apart from MIR typeck (as fact generation is somewhat in a single place there already, but should be cleaned up) into its own explicit module, with a single entry point instead of many.
There should be no behavior changes, and tests seem to behave the same as master: without polonius, with legacy polonius, with the in-tree polonius.
I've split everything into smaller logical commits for easier review, as it required quite a bit of code to be split and moved around, but it should all be trivial changes.
r? `@matthewjasper`
to help review, this duplicates the existing NLL + polonius constraint
generation component, before splitting them up to only do what they
individually need.
Refactor borrowck liveness values
This PR starts cleaning up `rustc_borrowck`, in particular around liveness values:
- refactors simple names that make no sense anymore: either referring to older structures using region elements, or to bitset containers and values.
- improves comments and fixes others
- removes unused return values and unneeded generic arguments
r? `@matthewjasper`
Currently we always do this:
```
use rustc_fluent_macro::fluent_messages;
...
fluent_messages! { "./example.ftl" }
```
But there is no need, we can just do this everywhere:
```
rustc_fluent_macro::fluent_messages! { "./example.ftl" }
```
which is shorter.
The `fluent_messages!` macro produces uses of
`crate::{D,Subd}iagnosticMessage`, which means that every crate using
the macro must have this import:
```
use rustc_errors::{DiagnosticMessage, SubdiagnosticMessage};
```
This commit changes the macro to instead use
`rustc_errors::{D,Subd}iagnosticMessage`, which avoids the need for the
imports.
Some types have a `body: &'mir Body<'tcx>` and some have `body: &'a
Body<'tcx>`. The former is more readable, so this commit converts some
fo the latter to the former.
By default, `newtype_index!` types get a default `Encodable`/`Decodable`
impl. You can opt out of this with `custom_encodable`. Opting out is the
opposite to how Rust normally works with autogenerated (derived) impls.
This commit inverts the behaviour, replacing `custom_encodable` with
`encodable` which opts into the default `Encodable`/`Decodable` impl.
Only 23 of the 59 `newtype_index!` occurrences need `encodable`.
Even better, there were eight crates with a dependency on
`rustc_serialize` just from unused default `Encodable`/`Decodable`
impls. This commit removes that dependency from those eight crates.
Fix early param lifetimes in generic_const_exprs
In cases like below, we never actually be able to capture region name for two reasons, first `'static` becomes anonymous lifetime and second we never capture region if it doesn't have a name so this results in ICE.
```
struct DataWrapper<'static> {
data: &'a [u8; Self::SIZE],
}
impl DataWrapper<'a> {
```
Fixes https://github.com/rust-lang/rust/issues/118021
Note about object lifetime defaults in does not live long enough error
This is a aspect of Rust that frequently trips up people who are not aware of it yet. This diagnostic attempts to explain what's happening and why the lifetime constraint, that was never mentioned in the source, arose.
The implementation feels a bit questionable, I'm not sure whether there are better ways to do this. There probably are.
fixes#117835
r? types
ignore implied bounds with placeholders
given the following code:
```rust
trait Trait {
type Ty<'a> where Self: 'a;
}
impl<T> Trait for T {
type Ty<'a> = () where Self: 'a;
}
struct Foo<T: Trait>(T)
where
for<'x> T::Ty<'x>: Sized;
```
when computing the implied bounds from `Foo<X>` we incorrectly get the bound `X: !x` from the normalization of ` for<'x> <X as Trait>::Ty::<'x>: Sized`. This is a a known bug! we shouldn't use the constraints that arise from normalization as implied bounds. See #109628.
Ignore these bounds for now. This should prevent later ICEs.
Fixes#112250Fixes#107409
